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    Backflow Preventer Installation & Testing in Essex, MD, Baltimore & 60-Mile Radius

    Protect Your Water Supply. Stay Code-Compliant. Ensure Safe, Clean Drinking Water.

    Serving Maryland homeowners and businesses since 2009. Office located in Essex, MD and operating within a 60-mile service radius.

    Schedule Your Backflow Inspection Today

    Call (410) 559-9514 for Immediate Backflow Service

    Protecting Your Water Supply

    If you own a home or business in the Essex or Baltimore, MD area, chances are that you rely on clean, safe water every single day. But without a properly installed backflow preventer, your plumbing system is at risk. Have you ever thought about what could happen if that water flowed in the wrong direction?

    When water reverses flow, known as backflow, contaminated water can seep into your clean supply. That contaminated water may carry bacteria, chemicals, viruses, and other harmful substances. The risks can include gastrointestinal illness, E. coli exposure, and serious plumbing damage.

    That’s where a backflow preventer comes in. It’s an essential device designed to stop contaminated water from flowing backward into your clean water supply.

    Whether you’re managing an apartment complex, operating a restaurant, or simply protecting your home, SM Mechanical provides professional backflow preventer installation and testing for both residential and commercial properties. We make sure your device is compliant, properly installed, and functioning as required. And it’s not just a smart investment – in many cases, it’s required by law.

    For complete residential and commercial plumbing support, visit our Plumbing Services page.

    Call Today for a FREE Backflow Assessment
    Serving Essex & Baltimore, MD

    Why Backflow Prevention & Backflow Devices Matter for Water Safety in Maryland

    Backflow occurs when changes in water pressure cause water to reverse direction inside your plumbing system. When this happens, contaminated water can enter sinks, showers, drinking fountains, or even your entire water supply.

    A backflow prevention device blocks this reverse flow if pressure changes occur, keeping your water safe and your plumbing system compliant with local codes.

    Backflow is not just a plumbing concern—it is a public health issue. According to WSSC Water, one of Maryland’s largest water utilities, backflow can introduce fertilizers, chemicals, bacteria, and other hazardous contaminants into clean water supplies.

    Because of these risks, backflow prevention devices are often required by Maryland plumbing codes and local authorities.

    At SM Mechanical plumbing services, serving the greater Baltimore, MD region within a 60-mile radius of our Essex office, we provide complete residential and commercial backflow services including installation, inspections, testing, repairs, and annual certifications. Our goal is to keep your water clean, your system protected, and your property compliant.

    What Type of Backflow Preventer Do You Need?

    There are several types of backflow preventers (sometimes called backflow valves). The right choice depends on your plumbing system, local requirements, and the level of contamination risk.

    • Atmospheric Vacuum Breakers (AVB)
      Commonly used in residential irrigation systems, sprinklers, and outdoor faucets. AVBs are simple, effective, and cost-efficient for low-risk applications.
    • Double Check Valve Assemblies (DCVA)
      Suitable for low-risk residential systems and some commercial properties such as offices or small retail locations. DCVAs provide moderate protection but are not designed for high-hazard environments.
    • Reduced Pressure Zone Assemblies (RPZ)
      Designed for high-hazard applications where contamination could cause serious health risks. RPZ units are commonly required in restaurants, commercial kitchens, car washes, medical facilities, and locations handling chemicals or biohazards.
    • Pressure Vacuum Breakers (PVB)
      Often used in lawn irrigation systems where slightly higher risk conditions exist than AVBs.
    • Hose Bib Vacuum Breakers
      Small devices that attach to outdoor faucets to prevent contaminated water from flowing back into your home’s plumbing system.

    Not sure which device you need? Our licensed technicians provide free evaluations and will recommend the correct solution based on your property and local code requirements.

    Local, Trusted & Professional Backflow Services

    SM Mechanical offers licensed backflow preventer installation, testing, repair, and certification. We have proudly served homeowners and businesses throughout Essex and the greater Baltimore, MD area for over 15 years.

    We are A-rated by the Better Business Bureau, recognized as a Best Home Project Company by HomeAdvisor, and proudly family-owned and operated. Whether you need annual certification or urgent service, you can trust our local experts.

    For emergency plumbing situations such as burst pipes or urgent water issues, visit our Emergency Plumbing page.

     

    Backflow Preventers (Valves) & Testing FAQs

    What’s the difference between a backflow preventer and a backflow valve?
    A backflow preventer is the full system designed to stop contaminated water from reversing flow. The term backflow valve is often used interchangeably but typically refers to individual components within that system.

    How often should backflow devices be tested?
    Most local regulations require annual backflow testing, particularly for RPZ assemblies. SM Mechanical performs inspections and required certification testing.

    What happens during a backflow test?
    A certified technician temporarily shuts off water, connects testing equipment, and checks pressure readings to confirm proper operation. Testing typically takes 30–60 minutes.

    Do you handle installation, testing, repair, and certification?
    Yes. SM Mechanical provides complete backflow services throughout the Baltimore, MD region within our 60-mile service area.

    Do I need a permit to install a backflow preventer in Maryland?
    In most cases, yes—especially for commercial properties or RPZ installations. We assist with permitting and ensure all work meets local code requirements.

    For additional information about water line protection and system integrity, visit our Water Line Plumbing Replacement page.

    Protect Your Water Supply

    Protect your water with expert backflow preventer installation, testing, and repair in Essex and the greater Baltimore, MD region.
    Call SM Mechanical at 410-559-9514 today to schedule service.

    This content has been reviewed for accuracy and approved by Purcell Oxendine, Plumbing Manager at SM Mechanical, LLC, who brings more than 18 years of hands-on industry experience. Last reviewed March 1, 2026.

    Want Plumbing Services That Are Worth Every Penny You Spend? Call Us!

    GET A FREE ESTIMATE As a family-owned and locally-operated company, SM Mechanical LLC will give you the kind of personalized plumbing services that we will offer our own family and friends. We also make sure that service appointments are very easy to make. Call us at or submit our very easy to use contact form. Rest assure that you will be contacted shortly to schedule an appointment for a free in-home consultation, inspection and estimate!
    What Our Customers Say
    I was referred for a humidifier and heating / AC service by a local real estate investor and fellow military veteran in Baltimore. Very impressed from call #1. Just as my referral said, SM mechanical is the "best of the best!"
    Wyatt E.Baltimore, Md
    Very personable and honest. Thoroughly explained every aspect of the job.
    Kerry C.Churchville, MD
    Friendly, fast, effective, and a great price. I couldn’t be happier.
    Virginia C.Catonsville, MD
    I appreciate the straight forward and honest approach that SM Mechanical took when explaining the work that needed to be done. I would definitely hired them again. It's nice to feel you have had your best interests kept in mind when you have work done in your home. Thanks again for wonderful customer service!
    Tiffany T.Abingdon, MD
    Very knowledgeable, fixed my problem quickly and at a fair price.
    Ralph G.Halethorpe, MD
    High quality equipment installed at competitive price. Made recommendations for getting most out of unit.
    Lawrence T.Dundalk, MD
    Next day service. The tech explain about the AC equipment and explained about the problem and how to fix it and what to do in the future. great customer service
    Elizabeth G.Gwynn Oak, MD
    Did not over-charge. Very informative and helpful.
    Lana R.Havre De Grace, MD
    Sean explained every detail of the job and took time to give me suggestions about placement. The duct installers were fast, efficient, competent and very polite. They were also very respectful of my time limitations
    Maureen T.Bel Air, MD
    Very knowledgeable. Determined the problem quickly and repaired. Didn't try to upsale or recommend replacement like a previous contractor. Would use again.
    John H.Baltimore, MD
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